Generally, the present invention relates to a switch. More particularly, the invention relates to a gravity actuated magnetic switch as might use in an illumination assembly under the hood of a motor vehicle.
In order to increase visibility during low light conditions, illumination assemblies have long been provided within the engine and trunk compartments of motor vehicles. For various reasons, including maximum illumination, these illumination assemblies are typically located on the under side or interior surface of the hood and trunk lid. The desire to increase operator convenience has resulted in the standard industry practice of providing these illumination assemblies so that they are automatically actuated by the raising and lowering of the hood or trunk lid itself.
Various mechanisms are presently used by the motor vehicle manufacturers to switch the illumination assemblies on and off. One variety of switching mechanism which has been widely used in the above and other applications is the plunger switch
Depending on the particular application, in this variety a plunger is released (or depressed) during the raising (or lowering) of the hood to close (or open) electrical contacts within the switch and illuminate (or turn off) the assembly.
One limitation associated with plunger switches is the need for positioning the switch where the plunger will be actuated by relative movement between two different structures of the vehicle, such as the hood and the interior frame of the engine compartment. Another limitation is the number of mechanical components needed in the switch and their corresponding potential for wear and failure.
Another variety of switch which has been extensively used to turn on and off the illumination assemblies associated with the engine and trunk compartments of a motor vehicles is the mercury switch. These switches contain a capsule in which two electrical contacts are physically spaced apart. The capsule is also partially filled with the liquid metal mercury. Upon the raising of the hood or trunk lid, the mercury flows into a position where it contacts both of the electrical terminals, establishes a conductive path between them, and energizes the illumination assembly.
Mercury switches, however, are not without their own limitations. With a continuing increase in the public's environmental awareness, the use of switches containing the highly toxic mercury has fallen and will probably continue to fall into disfavor.
From the above, it can be seen that there is a need and desire for a switch which is environmental friendly, simple in construction and not susceptible to significant wear problems of its associated hardware.
With the above limitations in mind, it is an object of the present invention to provide a switch assembly which is actuated in response to movement of the structure to which it is mounted.
Another object of this invention is to provide a switch assembly for use in an illumination system associated with a motor vehicle's engine and/or trunk compartments.
A further object of this invention is to provide an illumination system having a switch assembly which is actuated under the influence of gravity during the opening and closing of the vehicle hood and/or trunk lid.
Still another object of the present invention is to provide a switch assembly which is simple in construction and cost efficient to produce.
Another object of this invention is to provide a switch assembly which is environmentally friendly.
A further object of this invention is to provide an illumination system having a switch assembly which minimizes the use of mechanical components that are susceptible to wear and failure.
With the above and other objects in mind, the present invention broadly provides for a switch assembly which is actuated under the influence of gravity to turn on or off an illumination system a might be used in conjunction with the engine and trunk compartments of a motor vehicle. The switch assembly is therefore switchable between on and off positions solely in response to the raising and lowering of the hood or trunk lid. More particularly, it is the tilting of the switch assembly itself which causes the assembly to turn on and off.
In the switch assembly of the present invention, a magnet is retained within a housing in a manner which permits it to move between an "on" position and an "off" position as the assembly is tilted. When moved into its "on" position, the magnet is located adjacent to a switch or sensor which is induced, because of the magnet's proximity, to electrically close. When the hood or trunk lid is closed and the magnet is located in its "off" position, away from the switch or sensor, the assembly will be electrically open or closed thus operating the illumination system.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from the subsequent description of the preferred embodiments and the appended claims, taken in conjunction with the accompanying drawings.